Pump construction

ABSTRACT

A pump for viscous materials has two or more cylinders each of which accommodates a reciprocable piston. A receiving channel is adapted to receive material expelled from the respective cylinders and has an inlet for this purpose. A hopper contains viscous material and communicates via two apertures with the respective cylinders. A substantially S-shaped conduit is located in the hopper and has an outlet opening coaxial and communicating with the inlet, and an inlet opening. A shaft member is fast with the conduit and coaxial with the inlet, the shaft member being mounted for turning movement whereby it effects pivoting of the conduit between two end positions in which the inlet opening of the conduit respectively registers with one of the apertures. The pivoting movement is timed so that the inlet opening of the conduit registers with the aperture of that cylinder in which the piston is about to perform its working stroke.

United States P3tllt 1 Schellenberg PUMP CONSTRUCTION [75] Inventor: Wolfgang Schellenberg, Essen, Germany [73] Assignee: Torkret GmbH, Essen, Germany [22] Filed: July 14, 1971 [21] Appl. No.: 162,370

[30] Foreign Application Priority Data Jan. 29, 1971 Germany ..P 2104 191.8

[52] US. Cl ..4l7/5l7, 417/900 [51] Int. Cl ..F04b 15/02 [58] Field ofSearch ..4l7/516,517, 531, 417/532, 900

[56] References Cited UNITED STATES PATENTS 3,380,388 4/1968 Sherrod ..417/313 FOREIGN PATENTS OR APPLICATIONS 910,526 l/l946 France ..4l7/900 Apr. 10, 1973 Primary ExaminerC. J. Husar Assistant ExaminerLeonard Smith Attorney-Michael S Striker [57] ABSTRACT A pump for viscous materials has two or more cylinders each of which accommodates a reciprocable piston. A receiving channel is adapted to receive material expelled from the respective cylindersand has an inlet for this purpose. A hopper contains viscous material and communicates via two apertures with the respective cylinders. A substantially S-shaped conduit is located in the hopper and has an outlet opening coaxial and communicating with the inlet, and an inlet opening. A shaft member is fast with the conduit and coaxial with the inlet, the shaft member being mounted for turning movement whereby it effects pivoting of the conduit between two end posi tions in which the inlet opening of the conduit respectively registers with one of the apertures. The pivoting movement is timed so that the inlet opening of the conduit registers with the aperture of that cylinder in which the piston is about to perform its working stroke.

10 Claims, 6 Drawing Figures PATENTED 3,726,614

SHEET 1 BF 3 F/GZ INVENTOR. WoLFaAua HEUENBERG PATENTEDAPR 1 018B 3.726.614

sum 2 OF INVENTOR.

floLra/wa I'CHELLENBERG BY PATEHTEUAPM 01573 SHEET 3 OF '3 INVENTOR.

WOLFGANG SEHELLENBERG BY mm 3. 8M,

4 7 70km; y

PUMP CONSTRUCTION BACKGROUND OF THE INVENTION The present invention relates generally to a pump construction, and more particularly to a pump for viscous materials, such as concrete in its flowable state.

Pumps of the general type here under discussion are of course already known. Generally speaking they use two or more cylinders each of which has a piston reciprocably mounted therein, and a hopper in which the material to be pumped is accommodated and from which it is admitted into the respective cylinders via suitable apertures. A distributor is provided which alternately connects the cylinders with the channel or conduit which is to receive the pumped material from the cylinders. The cylinders operate alternately, meaning that when the piston of one cylinder performs its suction stroke and draws viscous material into the associated cylinder from the hopper, the piston of the other cylinder performs its working stroke and expels material from the associated cylinder into the receiving channel or conduit.

According to one embodiment known from the prior art the alternate connection of the cylinders with the hopper and the receiving channel is achieved by providing each cylinder with a separate sliding plate which is held and guided by two laterally mounted sliding rods. These extend to the exterior of the pump and are sealed at their ends by suitable sealing arrangements. However, even at a very low degree of wear these rods tend to draw quantities of the material to be pumped to the exterior, that is out of the respective cylinder. These quantities are usually in form of liquid and very fine particles of the material, and the loss of such water is facilitated by the fact that the material in the cylinders is in very high pressure during the operating stroke. Particularly when the viscous material being pumped is a concrete, that is a mixture of water and cement, the loss of matter will disadvantageously influence the composition of the concrete, not to mention the improper pumping operation itself. A rubber lip engages the sliding plate within the housing intermediate the openings for the hopper and the receiving channel, but cannot be adjusted for wear. Because of the structural configuration of this prior-art embodiment a uniform cross-section in the passage to the receiving channel is not possible, and this means that where the cross-section decreases the material must be forced through at high pressure which is. disadvantageous. Furthermore, the sliding plates must be moved at the expenditure of relatively high forces because it is necessary for them to pass through the viscous material which is itself under high pressure.

Another embodiment known from the art provides for a distributor in form of a single pivotable flap member which is utilized in a two-cylinder pump. In this construction, however, an even passage for the viscous material cannot be achieved, that is an even flow, and it is also not possible to provide for mechanical adjustments to compensate for wear of the flap member or sealing components associated therewith.

Finally, it has also been proposed to displace the entire cylinder of the pump in the direction towards the hopper and oppositely towards the inlet of the receiving channel, in order to overcome some of the disadvantages mentioned above. However, this requires very considerable technical expenditure resulting in a complicated expensive construction.

It is clear, therefore, that the prior art is in need of improvements which have not, however, heretofore been forthcoming.

SUMMARY OF THE INVENTION It is, accordingly, an object of the present invention to provide such improvement.

Particularly it is an object of the present invention to provide a pump of the type under discussion which avoids the disadvantages of the prior art.

Still more particularly it is an object of the present invention to provide such a pump for pumping of viscous material, particularly (but not exclusively) flowable concrete which is simple in its construction, can be assembled and disassembled in a simple manner and requires comparatively little maintenance which can be carried out readily and in a simple way.

A further object of the invention is to provide such an improved pump which has advantageous flow crosssections and which is sealed very tightly.

In pursuance of the above objects, and of others which will become apparent hereafter, one feature of the invention resides in a pump for viscous materials, particularly for concrete, which according to one embodiment comprises at least two cylinders each accommodating a reciprocable piston. A receiving channel is adapted to receive material expelled from the respective cylinders and has an inlet. A hopper is adapted to contain viscous material and communicates via two apertures with the respective cylinders. An S-shaped conduit is located in the hopper and has an outlet opening which is coaxial and in axial registry with the inlet, and further has an inlet opening. A shaft member fast with the conduit is coaxial with the inlet and journalled for movement in a sense pivoting the conduit between two end positions in each of which the inlet opening of the conduit registers with one of the apertures.

The S-shaped configuration of the conduit assures that over the entire length of the latter at all points there can be provided an approximately identical crosssection, a consideration which is highly advantageous in terms of affording advantageous flow of material. Furthermore, the pivoting of the conduit can be carried out in a very simple and highly effective manner, because the components which must be moved are under no or under very little pressure.

It is advantageous if the end of the conduit which is provided with the outlet opening is connected with the receiving channel at the inlet thereof by means of a coupling structure which permits not only pivotal but also axial movement of the conduit with reference to the inlet or receiving channel. In such a construction the shaft member (which is coaxial with the inlet) can be displaced axially of itself whereby the conduit itself can also be displaced axially of the inlet. This means that any play resulting from wear of the components can be readily adjusted. It is advantageous to connect the shaft member by means of a nut or the like with the frame in such a manner that such axial adjustment can be readily carried out, whereby a displacing of the nut will permit displacing of the shaft member in axial direction by the desired distance.

' engages the annular surface when the inlet opening is in registry with the respective aperture. Of course, the

wear rings could be of one piece with one another, but it is advantageous to make them separately to facilitate their replacement individually, because in this manner it is only necessary to pivot the conduit away from the aperture whose ring must be replaced. The wear which occurs on the respective wear rings can be compensated for by adjustment of the conduit via the shaft member to a certain extent, as well as via the pressure tight axially displaceable connection of the conduit with the receiving channel, and when the extent to which compensation can be made is exceeded, the wear ring is replaced.

According to a further embodiment of the invention it is possible to so arrange the conduit that the general plane of the inlet opening thereof extends in parallelism with the bottom of the hopper, thereby avoiding the danger that larger constituent components of the viscous material might become wedged against the conduit during the pivoting of the latter.

It is also possible, according to still another embodiment of the invention, to mount the conduit in a drum which has opposite open ends and with which it is fast (for instance by being of one piece therewith). The drum itself is so mounted that it can turn with reference to the housing having the two cylinders and provided in its end wall with the two apertures, and the bottom of the hopper. Of course the open ends of the drum must then be sealingly connected with the hopper and the end wall of the housing respectively. With such a construction the curvature of the substantially S-shaped conduit can be made still flatter and the conduit be made longer for less abrupt changes in the direction of flow of viscous material therethrough, and at the same time the construction of the pump overall can be lowered because the hopper can be made lower. Furthermore, this construction requires even lesser energy for pivoting the conduit and drum than the other constructions.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary diagrammatic sectional elevational illustrating one embodiment of the invention;

FIG. 2 is a detail view in a sectional elevational illustrating the distributor components of the embodiment in FIG. 1;

FIG. 3 is a view taken on line III-III of FIG. 1;

FIG. 4 is a sectional view on line IV-lV of FIG. 2;

FIG. 5 is a view similar to FIG. 1 illustrating a further embodiment of the invention; and

FIG. 6 is a section taken on line VI-Vl of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing firstly the embodiment in FIGS. 1-4 it will be seen that reference numerals 1 and 2 identify two cylinders of the novel pump, which extend in parallelism with one another and each of which accommodates a reciprocable piston 3. The pistons 3 in the two cylinders l and 2 move in mutually opposite directions,

meaning that while one of them performs a working stroke the other performs a suction stroke. In FIG. 1 only one of the cylinders and one of the pistons is visible but in FIG. 3 the relationship of the cylinders will become clearer.

Reference numeral 4 identifies the support or housing via which the cylinders 1 and 2 are connected with a hopper 5 for accommodation of a viscous material, for instance flowable concrete. The viscous material can of course be introduced into the hopper 5 in suitable manner which forms no part of the present invention.

Two openings 6 and 7 are provided by means of which the hopper 5 communicates with the housing 4 which in turn leads to the cylinders 1 and 2. Located within the hopper 5 is a distributor arrangement in form of a substantially S-shaped conduit 8. The inlet opening 9 of the conduit 8 cooperates with the openings 6 and 7, and the outlet opening 10 is coaxial with and associated with the inlet of the receiving channel or pressure conduit 11 which is to receive material expelled from the respective cylinders 1 and 2.

Reference numeral 12 identifies a coupling which sealingly connects the outlet 10 with the inlet of the channel or conduit 11, but which permits a pivoting movement of the conduit 8 about the axis of its outlet 10 as well as permitting an axial movement with respect to the inlet of the channel 11.

To effect such pivoting movement a shaft 13 is provided which is fast with the conduit 8, in the illustrated embodiment by being of one piece therewith. Of course, the shaft could also be a separate component which is connected in suitable manner with the conduit 8 so as to be fast therewith. In either case the shaft 13 is journalled in the support 14 for turning movement about its longitudinal axis, and it will be noticed that it is coaxial with the opening 10. The lower end portion of the shaft is provided with an external thread which is in turn engaged by a nut 15 (see FIG. 2) and which passes through the support 14. At the side of the support 14 which is remote from the conduit 8 the nut 15 is 7 located, with a slide bearing 16 being interposed between the nut 15 and the support 14. It will be noticed that by tightening the nut 15 the shaft 13 can be displaced in axial direction whereby a concomitant displacement of the conduit 8 is made possible in order to provide for wear which may take place between the annular surface surrounding the inlet opening 9 of the conduit 8 and the wear rings 17 which surround the respective openings 6 and 7, such wear resulting from contact with the annular surface The thus obtained mechanical adjustment and compensation for wear is not only very simple but also highly reliable, so that to all intents and purposes no escape of the material to be pumped can take place at the interface of the annular surface surrounding the inlet opening 9 and the wear rings 17 surrounding the respective openings 6 and 7.

FIG. 4 shows a hydraulic drive 18 which is connected via an arm 19, 19a with a portion 20 of the shaft 13 so that, when the drive 18 is operated, the shaft 13 is turned about its longitudinal axis in order to thereby pivot the shaft and concomitantly the conduit 8 to and fro between the two positions in which the opening 9 of the conduit 8 respectively registers with the openings 6 and 7.

In operation of the pump discussed above with respect to FIGS. 1-4, the conduit 8 is pivoted to and fro between its two end positions in which its inlet opening 9 respectively registers with the openings 6 and 7. Thus, the interior of the conduit 8 is alternately connected with the cylinder 1 and with the cylinder 2, so that the quantity of viscous material accommodated in the respective cylinder and expelled therefrom by the associated piston 3, is expelled through the conduit 8 and into the channel 11, whereas simultaneously the piston 3 of the other cylinder sucks material from the hopper 5 through the associated opening (if the opening 6 communicates with the inlet opening 9, then material will be sucked into the other cylinder via the opening 7, and vice versa).

A further embodiment of the invention is illustrated in FIGS. 5 and 6. Here, the substantially S-shaped conduit 8 is again of one piece with the shaft 13, but in addition it is also of one piece with a drum 21. The shaft 13 is mounted and turnable in the same manner as discussed above with respect to the embodiment of FIGS. 1-4.

In FIGS. 5 and 6, however, the drum 21 pivots about its longitudinal axis that is connected at its opposite axial ends via seals 22 of suitable construction with the hopper 5 on the one hand and the frame or housing 14 of the pump on the other hand. Pivoting of the drum 21 of course alternately brings the inlet opening 9 of the conduit 8 into communication with the openings 6 or 7 in the end wall of the fragmentarily illustrated support or housing 14, this end wall being identified with reference numeral 20.

The embodiment of FIGS. 5 and 6 has the advantage that the curvature of the conduit 8 is flatter than is possible in the embodiment of FIGS. 1-4, and that the hopper 5 can be lower. An additional advantage is the fact that less force is required for pivoting the drum with the conduit 8. The material which is accommodated in the drum is turned along with the latter and must not be displaced in the drum by the moving conduit 8, as would be the case if the conduit 8 were movable relative to the drum. The fact that the seals 22 must be provided is of no importance and any suitable seal can be utilized, because the material in the drum 21 is not under pressure so that no particular forces must be accommodated by these seals.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in a pump construction, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

1. In a pump for viscous materials, particularly for concrete, in combination, at least two cylinders each accommodating a reciprocable piston; a receiving channel adapted to receive material expelled from the respective cylinders, and having an inlet; a hopper adapted to contain viscous material and communicating via two apertures with the respective cylinders; a curved conduit in said hopper having an outlet opening coaxial and axially registering with said inlet, and an inlet opening; a shaft member fast with said conduit and coaxial with said inlet, said shaft member being journalled for movement in a sense pivoting said conduit between two end positions in each of which said inlet opening registers with one of said apertures; and displacing means for displacing said shaft member in axial direction of the same.

2. In a pump as defined in claim 1; further comprising support means journalling said shaft member for said movement thereof.

3. In a pump as defined in claim 1; and further com- I prising coupling means coupling said conduit with said channel for rotatable and axial displacement relative to said inlet.

4. In a pump as defined in claim 1; said conduit being substantially S-shaped.

5. In a pump as defined in claim 1, said displacing means comprising nut means.

6. In a pump as defined in claim 1; and further comprising turning means connected with said shaft for turning the same about the axis thereof.

7. In a pump as defined in claim 1, said hopper having an open end and a closed end provided with an endwall having said apertures; and wherein the general plane of said inlet opening parallels the general plane of said endwall.

8. In a pump as defined in claim '7, wherein said general planes extend at least substantially horizontal.

9. In a'pump for viscous materials, particularly for concrete, in combination, at least two cylinders each accommodating a reciprocable piston; a receiving channel adapted to receive material expelled from the respective cylinders, and having an inlet; a hopper adapted to contain viscous material and communicating via two apertures with the respective cylinders; a curved conduit in said hopper having an outlet opening coaxial and axially registering with said inlet, and an inlet opening, said conduit having an annular surface surrounding said inlet opening; a pair of wear rings each releasably surrounding one of said apertures and adapted for sealing engagement with said annular surface in response to registry of said inlet opening with the respective aperture; and a shaft member fast with said conduit and coaxial with said inlet, said shaft member being journalled for movement in a sense pivoting said conduit between two end positions in each of which said inlet opening registers with one of said apertures.

' having an outlet opening coaxial and axially registering with said. inlet, and an inlet opening; a drum fixed to and turnable with said conduit and having opposite open ends sealingly connected with said bottom portion of said hopper and with said endwall of said casing radially outwardly of said apertures; and a shaft member fast with said conduit and coaxial with said inlet, said shaft member being journalled for movement in a sense pivoting said conduit'between two end positions in each of which said inlet opening registers with one of said apertures. 

1. In a pump for viscous materials, particularly for concrete, in combination, at least two cylinders each accommodating a reciprocable piston; a receiving channel adapted to receive material expelled from the respective cylinders, and having an inlet; a hopper adapted to contain viscous material and communicating via two apertures with the respective cylinders; a curved conduit in said hopper having an outlet opening coaxial and axially registering with said inlet, and an inlet opening; a shaft member fast with said conduit and coaxial with said inlet, said shaft member being journalled for movement in a sense pivoting said conduit between two end positions in each of which said inlet opening registers with one of said apertures; and displacing means for displacing said shaft member in axial direction of the same.
 2. In a pump as defined in claim 1; further comprising support means journalling said shaft member for said movement thereof.
 3. In a pump as defined in claim 1; and further comprising coupling means coupling said conduit with said channel for rotatable and axial displacement relative to said inlet.
 4. In a pump as defined in claim 1; said conduit being substantially S-shaped.
 5. In a pump as defined in claim 1, said displacing means comprising nut means.
 6. In a pump as defined in claim 1; and further comprising turning means connected with said shaft for turning the same about the axis thereof.
 7. In a pump as defined in claim 1, said hopper having an open end and a closed end provided with an endwall having said apertures; and wherein the general plane of said inlet opening parallels the general plane of said endwall.
 8. In a pump as defined in claim 7, wherein said general planes extend at least substantially horizontal.
 9. In a pump for viscous materials, particularly for concrete, in combination, at least two cylinders each accommodating a reciprocable piston; a receiving channel adapted to receive material expelled from the respective cylinders, and having an inlet; a hopper adapted to contain viscous material and communicating via two apertures with the respective cylinders; a curved conduit in said hopper having an outlet opening coaxial and axially registering with said inlet, and an inlet opening, said conduit having an annular surface surrounding said inlet opening; a pair of wear rings each releasably surrounding one of said apertures and adapted for sealing engagement with said annular surface in response to registry of said inlet opening with the respective aperture; and a shaft member fast with said conduit and coaxial with said inlet, said shaft member being journalled for movement in a sense pivoting said conduit between two end positions in each of which said inlet opening registers with one of said apertures.
 10. In a pump for viscous materials, particularly for concrete, in combination, at least two cylinders each accommodating a reciprocable piston; a receiving channel adapted to receive material expelled from the respective cylinders, and having an inlet; a casing provided with said cylinders and having an endwall provided with two apertures; a hopper adapted to contain viscous material and having a bottom portion, said hopper communicating via said two apertures with the respective cylinders; a curved conduit in said hopper having an outlet opening coaxial and axially registering with said inlet, and an inlet opening; a drum fixed to and turnable with said conduit and having opposite open ends sealingly connected with said bottom portion of said hopper and with said endwall of said casing radially outwardly of said apertures; and a shaft member fast with said conduit and coaxial with said inlet, said shaft member being journalled for movement in a sense pivoting said conduit between two end positions in each of which said inlet opening registers with one of said apertures. 